2018 Kia Optima: excessive oil consumption

Filed Jun 25, 2026 · Engine · MO

The car burns oil within a week of getting an oil change. It was only driven a 200 miles before all of the oil was burned out. This has been a consistent issue with this car that the oil burns at an extreme rate. This is a safety risk as it could lead to engine overheating, the engine could stall out due to the fast burning of the oil, or a potential fire hazard while driving. The oil light will come on for a second and at that point, the oil is already EXTREMELY too low. I brought the car to the mechanic and they have told me multiple times that there is no leak or anything. The mechanic says that the car simply is burning oil too fast.

Filed May 6, 2026 · Engine, Locks · 121,000 miles · OK

The contact owns a 2018 Kia Optima. The contact stated that while attempting to accelerate from a standing start the vehicle had experience sever jerking and hesitation. Also, the vehicle has experience oil consumption problems and the contact constantly added engine oil. The cause of the failures were not determine. Also, the hood latch had malfunctioned and the hood could not opened to add oil to the engine. The cause of the failures were not determined. The local dealer and manufacturer were notified of the failures but no assistance was offered. The failure mileage was 121,000.

Filed Apr 28, 2026 · Engine · VA

2018 Kia Optima LX, 2.4L GDI Theta II engine. Approximately 128,000 miles. Reporting severe internal oil consumption that has progressed to engine misfire and shaking, consistent with late-stage Theta II connecting rod bearing failure. The vehicle is now unsafe to drive and has been parked. Timeline: Purchased as a Certified Pre-Owned vehicle in December 2021. Excessive oil consumption began shortly after purchase. For approximately 4.5 years I have added about 1 quart of oil every 2 weeks to keep the engine from running dry. No external leaks have ever been found by any mechanic. Multiple independent mechanics attempted diagnosis and repair over this period. None resolved the issue. The vehicle has now developed a pronounced shake and apparent engine misfire, the textbook progression to rod bearing failure documented in the federal safety agency investigation PE19-004 and prior recalls/campaigns 17V‑224, SC147, and SC172. Safety concerns: Sudden engine seizure or stall at highway speed creates a serious crash risk for me and surrounding traffic. Theta II 2.4L GDI rod bearing failure has been associated with under-hood fires. The defect develops gradually with no warning to the driver beyond elevated oil consumption, which is frequently dismissed as normal until catastrophic failure occurs. I am filing this complaint to document the failure and to add to the federal safety agency's data on the Theta II GDI 2.4L engine in 2018–2019 Optimas. This model year was excluded from the original 2017 recall but is included in the Hyundai and Kia Engine Litigation class settlement and the lifetime engine warranty extension. My vehicle's symptoms match the defect pattern exactly. I will pursue warranty engine replacement, but I want this safety failure on the federal record regardless of how Kia responds.

Filed Apr 15, 2026 · Engine · GA

Consuming fuel to the amount of roughly 1/2 quart per 150 miles. Vehicle has been inspected by mechanic and the oil pan, oil filter, and PCV valve has been replaced and engine oil UV dye added and cycled with no leaks found. The risk is that if not rigorously checked often, the engine will malfunction because the car runs out of oil. I have had my mechanic checking this car since I purchased it in January 2026. We have had to replace the oil pan and do two full oil changes with three separate quarts of oil being added in between all of that to keep it topped up. My mechanic agrees that the engine is consuming oil at an extremely high rate. My mechanic and a mechanic at the dealership where I purchased it are the only one who has inspected the car for this issue so far. The mechanic at the dealership is who recommended we replace the oil pan to see if that fixed the leak, which my personal mechanic did. Yes the critical engine failure lamp illuminates on the dashboard when the oil ran out the first time while I was driving it. This was how I discovered that there was an oil leak. This specific incident occurred three weeks after I purchased the car which I bought in mid-January of 2026.

Filed Mar 11, 2026 · Body, Engine · GA

My teenage daughter regularly drives this vehicle. The vehicle began experiencing significant oil consumption, oil leaks, and intermittent loss of power. During an early inspection at an independent repair facility, a check engine code P1326 was identified. Due to the symptoms and diagnostic code, the repair facility advised that the vehicle could be heading toward engine failure and recommended that the vehicle be taken to an authorized dealership because potential engine issues may fall under manufacturer warranty coverage. The vehicle was then towed to an authorized dealership. During the first visit, the dealership retained the vehicle for an extended period of time, approximately two months. During that visit, several recommended services were completed, including replacement of spark plugs, ignition wires, and replacement of the valve cover gasket along with other recommended maintenance. During that visit, it was also stated that the vehicle has a known issue with excessive oil consumption. Because of this, the oil level is checked weekly and oil is added as needed. I also informed the dealership that the independent repair facility had identified code P1326, but I was told that the dealership diagnostic codes were different. After these repairs, the vehicle experienced another incident where it lost power and began idling roughly while being driven on a busy highway. The vehicle was taken back to the dealership. During that visit, it was stated that the fuel injector harness and oil pressure sensor needed to be replaced. The dealership also indicated that the spark plugs needed to be replaced again, even though they had been replaced at the same dealership less than a year earlier. At that time, I asked if the vehicle would be safe to drive for approximately one week because I needed to travel out of town and my daughter would need the vehicle. The dealership advised that it was safe to drive during that time. The vehicle was then brought back to the deal

Filed Jan 9, 2026 · Engine · GA

It started with the oil. I constantly have to add oil. when it first started that’s what I was doing just adding oil. Then it got worse the engine light started to come on and it no longer gives me the low oil warning. I took it to the dealership and it was there for about three weeks. They said that the car needed a system update, they updated it and i took it home after that. Its been about a year since then and my car is still having the same issue and getting worse. I had to change the spark plugs a few times since then i also have oil coming out the back pipe and it’s been doing this since before I took it to the dealership. I also had to spend money on a rental car while it was at the dealership.

Filed Jan 8, 2026 · Brakes, Electrical · GA

I turned the car off, it had difficulty turning back on and the brake pedal got really hard. I had to wait about 30-45 minutes and then I was able to get the car started and brake pedal back to normal and no lights. Recently, I left the car on to run into a shop real quick and come back out. When I got back to the car, the power steering light, battery, and warning light?(amber triangle with ! In the center of it) were all on. I rev the engine and the issue went away for a quick second but then came back on. To avoid turning my car off and being stuck, I just shift to reverse and tried to leave. I’m backing out of the spot and now the backup camera is going in and out lights flashing on the dash and I’m trying to brake but the brake pedal isn’t registering and next thing you know, I’ve backed into a guard rail. On the way to drop my kids off at the babysitter, I was coming to a stop sign, and my car wouldn’t brake, i went through oncoming trafic and had to run off the road. KIA did a multi point inspection a few months apart from one another. One the car tested fine, then the second time they are saying a brake booster and no engine oil in the vehicle and that the car is basically trash. The oil light goes on and off and I can smell burning oil. I still owe 7 grand on this car and I just bought it last year and it was seamingly fine.

Filed Oct 7, 2025 · Engine · IA

I’ve had my car for 6 months and it constantly burns oil I’ve had 4 oil changes because it Is completely disappearing but my mechanics can not find any leaks. Then I changed all my spark plugs and two were completely burnt and they were changed a month ago and now one of them went again and this time is completely covered in oil

Filed Sep 28, 2025 · Engine · LA

The engine of my 2018 Kia Optima is burning oil. When it started, I had 72,000 miles, and it's burning one quart of oil every thousand miles. There is no oil leak. I will take it back to Kia on October 2, 2025. The mechanic reported that it has an internal engine issue.

Filed Sep 24, 2025 · Engine · CA

The oil consumption is burning at a faster rate than normal. My oil changes are always on time but for months I have been having to take it for an oil change about 2,000 miles below mileage time. I have had it inspected but found no oil leaks. This is a major problem for the engine and safety.

Filed Jul 18, 2025 · Engine, Fuel system · GA

My 2018 Kia Optima LX began using excessive oil (>3 quarts/1000 miles) just over 100K miles. I researched and found that the Theta II engine in my car is known for this. When I took my car to dealership (Stokes Hodges Kia, North Augusta, SC), with the check engine light on, they told me me plugs were fouled (they were just replaced 1 yr prior), cylinder 3 misfiring, and that I needed to pay a few thousand dollars to have repaired. When I asked them to guarantee the soaking process they recommended, they responded that they couldn't, that it "only worked 80% of the time." I have the KSDS download since 2019 and asked them to follow the guidelines of their TSB ENG 222 for the class action lawsuit and start a 1000 mile oil consumption test. they refused, basically telling me the only way to get a new engine from Kia, since my car is over 100K miles, is to drive it until the engine seizes. I expressed my fear for personal safety, but they wouldn't help me. I am original owner and have all services, etc documented. I called Kia customer affairs, then was told only local dealership could help. they stuck me in a loop between them without helping. Please help me.

Filed Jul 15, 2025 · Engine · CA

Kia is aware of the engine oil consumption causing misfires, failed emissions test, blowing a rod and engine lock up. Their solution was a class action lawsuit that state once the car is locked up or rod has blown through the engine then they will fix it. I have had to add oil at least 3 times every 3000 miles and continue to replace the oil filter as well. The spark plugs have been replaced mutliple times also to help with this issue. Kia advised that my vehicle did not fall under this recall even though my vehichle is having the same issues as the recall states. This is a known issue with this make and model and they should not be able to get away with selling defective vehicles and not repairing the issues they knew they had prior to selling the vehicles. Something needs to be done.